The present invention relates to supporting structures generally and, more particularly, to a novel suspending supporting structure for supporting substantially rigid linear structures such as pipelines, tramways, walkway bridges, transportation galleries, underwater tunnels, etc placed above a surface.
While the present invention is described in detail with reference to the support of pipelines, it will be understood that it is application as well to the support of other substantially rigid linear structures such as pipelines, tramways, walkway bridges, transportation galleries, underwater tunnels, and etc.
Design and construction of supports for linear structures such as pipelines, tramways, walkway bridges, transportation galleries, underwater tunnels, etc. placed in complex terrain, or underwater, or in ecologically sensitive areas with long-term recovery of soils destroyed by construction activities, have a long term experience.
Depending on the linear structure, different types of supports are currently in use. For example, aerial and underwater pipelines are placed mostly in trenches dug in the ground and then backfilled, sleepers placed upon the ground, or tower supports. Tramways and walkway bridges, as well as transportation galleries, are usually supported by towers or by suspended long-span cable systems.
However all these types of supports have significant drawbacks under the above conditions.
For example, feasibility and cost effectiveness of placing of the pipelines underground or supporting them by sleepers strongly depends on ground conditions: hardness and roughness of the ground. For many cases of irregular terrain, using these supports is completely impossible. Similar restrictions exist for using tower supports. Placed across mountainous areas with steep slopes and high peaks, they are ineffective because their heights are significantly higher than the cost effectiveness limits (approx. 100-150 ft). Practically, designers prefer to bypass such areas even though it increases the lengths of the linear structures and accordingly, their costs. Both, sleepers and towers are highly vulnerable to natural disasters such as snowfalls, landslides, earthquakes, etc., typical occurrences in mountainous areas.
The suspended systems are more suitable for complex terrain but they are used rarely. The main problem of these structures is that the main carrying cable and the suspended linear structures have low lateral stiffness and are subjected to large displacements and rocking under the lateral loads, mostly wind. To increase the stiffness, traditional suspended systems include special structures such as horizontal frames or a number of horizontally interconnected cables, or the like. See U.S. Pat. Nos. 3,604,361 and 3,745,601. As a result, suspended supporting systems usually fail cost competition with sleepers and tower supports
An effective system of suspended supports for aerial transportation means, such as ski lifts, aerial tramways, freight ropeways, etc is described in U.S. Pat. No. 5,655,457. The system described therein includes a long-span cable suspended at its ends and placed along the transportation route A number of spaced apart supports for the aerial means are hung from the cable. Each support has a rigid element supporting the transportation means carried by the cable and guy ropes, one end of which is attached to the rigid element and another end is anchored in the ground and tensioned. The guy ropes carry lateral loads applied to the rigid-elements. No additional structures increasing the lateral stiffness of the system are required. The system is very effective for aerial transportation means; however, for carrying linear structures it has to be essentially modified.
Accordingly, an object of the present invention is to provide a suspended supporting system for linear structures such as pipelines, tramways, walkway bridges, transportation galleries, underwater tunnels, etc, providing lateral stability of the structures by segmenting them and thus, decreasing their free spans in horizontal plane. The most effective areas of application of the system are complex terrain and underwater conditions, as well as ecologically sensitive areas with long-term recovery of soils destroyed by construction activities
A suspended supporting system for supporting a substantially rigid linear structure such as a pipeline, a tramway, a walkway bridge, a transportation gallery, an underwater tunnel, etc. placed above ground/seabed/riverbed, said system comprising means attached to said linear structure, pulling said linear structure upward, generating upward vertical force of magnitude great enough for carrying downward vertical loads and lateral loads applied to the said linear structure, and at least two guy ropes placed at angle with each other, upper ends of which are attached to said linear structure and lower ends of which are attached to a footing structure placed on or anchored in said ground/seabed/riverbed.